strip package scope in safePackageName function

package.json

@@ -73,6 +73,7 @@
     "@types/camelcase": "^5.2.0",
     "@types/execa": "^0.9.0",
     "@types/fs-extra": "^7.0.0",
+    "@types/jest": "^24.0.15",
     "@types/mkdirp": "^0.5.2",
     "@types/ms": "^0.7.30",
     "@types/node": "^12.0.2",

src/utils.ts

@@ -14,7 +14,9 @@ export const safeVariableName = (name: string) =>
   );
 
 export const safePackageName = (name: string) =>
-  name.toLowerCase().replace(/((^[^a-zA-Z]+)|[^\w.-])|([^a-zA-Z0-9]+$)/g, '');
+  name
+    .toLowerCase()
+    .replace(/(^@.*\/)|((^[^a-zA-Z]+)|[^\w.-])|([^a-zA-Z0-9]+$)/g, '');
 
 export const external = (id: string) =>
   !id.startsWith('.') && !path.isAbsolute(id);

test/jest.config.json

@@ -1,7 +1,8 @@
 {
   "roots": ["<rootDir>/tests"],
   "collectCoverageFrom": ["**/*.js"],
-  "testMatch": [
-    "<rootDir>/tests/**/?(*.)(spec|test).(ts|js)?(x)"
-  ]
-}
+  "transform": {
+    "^.+\\.ts?$": "ts-jest"
+  },
+  "testMatch": ["<rootDir>/tests/**/?(*.)(spec|test).(ts|js)?(x)"]
+}

test/tests/utils-safePackageName.test.ts

@@ -0,0 +1,9 @@
+const { safePackageName } = require('../../src/utils');
+
+describe('utils | safePackageName', () => {
+  it('should generate safe package name', () => {
+    expect(safePackageName('@babel/core')).toBe('core');
+    expect(safePackageName('react')).toBe('react');
+    expect(safePackageName('react-dom')).toBe('react-dom');
+  });
+});